This invention relates to hydrogenated copolymers. In another aspect this invention relates to hydrogenated 1,3-cyclohexadiene/1,3-butadiene copolymers.
Essentially random copolymers of 1,3-cyclohexadiene and 1,3-butadiene at a weight ratio in the range of about 40/60 to about 60/40 have been prepared which have relatively low green tensile strength. A low green tensile strength is a general characteristic of random copolymers, e.g. butadiene/styrene random copolymers. Likewise, hydrogenated counterparts of random copolymers, e.g. butadiene/styrene random copolymers, also have relatively low green tensile strength. Surprisingly, it has been discovered that when copolymers of 1,3-cyclohexadiene/1,3-butadiene, prepared as indicated below, are hydrogenated, the green tensile strength is unexpectedly higher than that of the parent (unhydrogenated) copolymer.
Accordingly, it is an object of this invention to provide hydrogenated 1,3-cyclohexadiene/1,3-butadiene copolymers having unusual green tensile strength.
Further it is an object of this invention to provide a method for increasing the green tensile strength of essentially random copolymers of 1,3-cyclohexadiene and 1,3-butadiene.
Further aspects, objects and advantages of the invention will become apparent to one skilled in the art upon studying the specification and appended claims.